Posts by slateboy

    i have the paint audio midi cap std too. A great unit for the price and has flexible functionality. Not yet convinced with the KPP mode as it requires press+hold for moving banks which is not practical during a live show. However the super/geerk mode works nicely.

    see here:

    I also had the mvave unit too. Great for very basic use but the downside is that it works in banks of four whereas the kemper is grouped in banks of five. but quite neat and compact and relatively cheap.

    It appears that pressing the bass/middle/treble knobs on the player shows its current value. "Push and hold" on the gain or volume shows the value of that parameter (both knobs have dual-parameter control) so be nice to have similar on the bass/mid/treb too.

    How about a double-press or press+hold shows the "saved" value of those parameters or perhaps a double-press resets that parameter to its saved value?

    Its nice having the visual feedback of the current value but, like on other units, sometimes handy to know what the initial/saved value was.

    I guess there is the potential for these knobs to do other functions when pressed+turned, like the gain and volume knobs currently do. I bet Kemper have something in mind

    what power-supply are you using?

    I have experienced this when the power-supply gets momentarily interrupted (possibly knocked or wiggled)

    Can you check the mains supply feeding this as well as the physical security of the DC plug in the back of the player?

    Has it had a nasty knock or something dropped on it?

    check this thread out:

    Goodmorning everyone, I am sorry that I had not seen this post before. I have still not read all the messages, but if still needded the answer is yes. I created a midi controller with arduino Micro and it works with only one usb cable (no extra power or midi required). But you need an Arduino with us midi capability, and there is only the Micro, the Leonardo and maybe another one. I planned to write a thread about it, but I am postponing it since a lot of weeks. Just remember to insert use the library MidiUSB.h and not the normal one. I also wrote some functions to send NRPN, SysEx and manage their value with a Potentiometer, so it is possible.

    Did you have to reflash the Arduino firmware? Be interested to learn about the connectivity as a USB device with the kemper

    i did share some sysex code for this here:

    February 22, 2024 at 4:08 PM

    SEND call for rig name

    F0 00 20 33 02 7F 43 00 00 01 F7
    (you already got this)

    What are you receiving back and how are you dealing with that data?

    So, i am sending 0xF0, 0x00, 0x20, 0x33, 0x02, 0x7F, 0x43, 0x00, 0x00, 0x01, 0xF7 which according to the manual is the sysex to request the current values of the rig name but all i get for response is the same exact sysex, it's not including the rig name for some reason, do i have to send anything else besides that sysex?

    EDIT: I managed to send and receive the messages via software, i need to figure out/find what the performance name sysex is, and find out what's wrong with my code, but we're getting closer!

    check you not got a midi-through enabled sending back exactly what you send out

    no worries, i'm starting to make it work, it's taking time, but it's ok, i managed to send sysex and receive them and print on the screen, but i think i have to get it translated or something, cause i'm getting the sysex message as it is, i'll figure it out eventually hahaha


    It will get returned as another sysex message with the text encoded as ascii characters. Your mission is to extract the hex digits that represent the characters within the sysex message and then convert each into a readable character then output as astring.

    SYSEX RECEIVED/returned rig name
    F0 00 20 33 00 00 03 00 00 01 47 75 79 74 72 6F 6E 20 54 20 32 00 F7
    name/string part (from above) = 47 75 79 74 72 6F 6E 20 54 20 32
    decoded acsci characters:
    G  u  y  t  r  o  n     T     2
    (btw, 20 is a space character)

    Are we sure sending sysex via USB is doable at this point? I've been trying stuff all day and nothing worked, i can't even make the arduino to send sysex, of course not talking about reading them...

    I have not done any midi to/from the kemper over USB. I have not reached the stage where i have made (reflashed the arduino to create) a class-compliant (recognisable) USB-midi device. I am only as far as midi over the standard 5-pin, so unable to comment. Sorry.

    This is starting to seem pretty hard, i'm ok with "only" using CCs instead od nrpn and the issue with having to press twice for effects is not really too nanoying, i barely enable/disable stuff, but i'd like to use the screen to retrieve info from the kemper, i've been researching for a while, no luck so far

    Yes, it can be heavy-going! Take a look at this thread:

    February 22, 2024 at 4:08 PM

    1) If i use the controller to switch between rigs in performance mode, go performance up/down, enable the tuner and turn effects on/off, what's the advantage of using nrpn agains normal CCs as i was using?

    no advantage, i dont think, just use whatever is easier and does the job

    2) My code was not acting properly since the beggining, it wasn't "remembering" the effect status, so some times to turn effects on/off i have to press the button twice (let's say delay is off, i press once, the arduino sends off CC, so it does nothing, and then i have to press it again to turn it on) is there a workaround for that? It's not a big issue for me since i don't play live or anything, but it would be cool to get it fixed.

    unless you have two-way communication to read the state of the Kemper (which makes it much more complex) you need to assume the state of effects when selecting a new rig (program/slot change) and start with your arduino in that assumed/reset state

    3) Any idea how could i make the screen to show kemper info? Mostly performance in one row and rig name on the second one, i dont need too much stuff.


    you need to send a system exclusive message to retrieve the information which will be returned as another sysex message which you need to de-code and convert it into text. This is next-level midi stuff so make sure youre happy with the first two items first. Alternatively (and much easier) you could "assume" the names-per-bank/slot in the arduino and present these on the screen.

    I already tried with 31250 but the kemper still freezed, i have no idea why

    Have you got some kind of midi monitor device? Worth checking if there is any unwanted midi data or other noise getting sent that is not required. or perhaps it is sending/getting incomplete midi messages?

    Or maybe (as i have had in the past) the ardiuno is stalling and not sending out a steady/even flow of midi data. I found that constantly updating the screen on the arduino LCD takes a lot of processing-power that affects midi transmission and better to update the display only when needed, ie a change of data. Therefore the priority is prioritising midi data flow rather than a visual.

    here's a nice bit of bedtime reading on the subject:

    December 14, 2023 at 4:55 AM